Starting in the late 1990s, injection drug use, primarily of heroin, has become widespread in Dar es Salaam, Tanzania, threatening to reverse a declining HIV epidemic through increased drug-associated HIV transmission. An estimated 50,000 people who inject drugs (PWID) live in Tanzania. In Dar es Salaam, 42% are estimated to be HIV infected, compared to 9% overall in the general population. Supported by the United States Centers for Disease Control and implemented by the members of this research group, medication assisted treatment services, specifically with methadone, are currently being established in Tanzania. To date, 2 clinics have been opened in Dar es Salaam, enrolling 1,010 clients into methadone services. Given the rapid enrollment of PWID into methadone and high burden of HIV, the methadone clinic provides a unique opportunity to provide comprehensive HIV treatment and care to this key population. However, only 35% of MAT clients who are HIV-positive are receiving CD4 results within 30 days of their HIV test and only 11% of those who are eligible are initiating antiretroviral therapy within 30 days of CD4 screening. To improve ART initiation among this at-risk population, we propose the Integrated Methadone and Antiretroviral Therapy strategy (IMAT) based on the PRECEDE framework of predisposing, enabling, and reinforcing factors for health program planning. IMAT uses 1) targeted knowledge transfer for providers that predispose them to timely ART initiation, 2) point-of-care CD4 count screening for providers that enable ART initiation and 3) alerts and reminders for providers that reinforce ART initiation. We propose to develop and pilot the IMAT strategy in the methadone clinic at Muhimbili National Hospital, and in doing so, we anticipate building a functional model of methadone and ART integration that improves the effectiveness and efficiency of service delivery for PWIDs in Tanzania. The specific aims of this proposal are to: 1) describe predisposing, enabling, and reinforcing factors related to the integration of HIV care and treatment into methadone treatment with in-depth interviews and patient surveys, 2) implement and examine the effectiveness of IMAT on CD4 screening and ART initiation with a pre-post study design, and 3) assess the feasibility and acceptability of the IMAT strategy with in-depth interviews as well as patient satisfaction and time-motion surveys. Our research group has established the first publically funded methadone program on the mainland of sub-Saharan Africa; however, challenges remain in addressing the disproportionate HIV burden amongst PWID. Using the PRECEDE framework, we aim to develop an effective model of methadone and HIV treatment integration among this population of methadone clients with a high HIV prevalence. This setting will enable us to adequately address the proposed study questions, and the results from this research will contribute to the evidence-base for integration that can be applicable to MAT programs not only in Tanzania but also in the United States and throughout the world.